Forecasters say the tropical storm known as Bud has evolved into a hurricane in the Pacific Ocean off the southwestern coast of Mexico.

The U.S. National Hurricane Center in Miami says the storm is carrying maximum sustained winds of 120 kilometers an hour, making it a category one storm on the scale that measures a storm's potential destructive power. Forecasters expect the center of Hurricane Bud to reach landfall by late Friday, and cause swells that are likely to cause life-threatening conditions along the surf.

Mexico City has issued a tropical storm watch along the Pacific Coast from Punta San Telmo to La Fortuna.